\documentclass{standalone}
\usepackage{tikz}
\usepackage{ctex,siunitx}
\setCJKmainfont{Noto Serif CJK SC}
\usepackage{tkz-euclide}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{circuitikz}
\usetikzlibrary{patterns, calc}
\usetikzlibrary {decorations.pathmorphing, decorations.pathreplacing, decorations.shapes}
\ctikzset{bipoles/length=1cm}
\begin{document}
\small
\begin{circuitikz}[>=latex, scale=1.0,european]
  % \useasboundingbox(0.9,0)rectangle(5.1,5);
  \draw(0,1.5)to [R] (6,1.5);  \draw [->](0,1.5)--(2,1.5)node [above]{$I$};
  \draw(0,0)to [R] (6,0);  \draw [->](0,0)--(.5,0)node [above]{$I$};
  \draw [->](1,0)--(1.75,0)node [above]{$I_1$};
  \draw [->](1,-1)--(1.75,-1)node [above]{$I_2$};
  \draw (1,0)--(1,-1) to [R=$R$] (5,-1)--(5,0);
  \draw [fill=black](1,0) circle (2pt);
  \draw [fill=black](5,0) circle (2pt);
\end{circuitikz}
\end{document}